Materials
Resources needed include images of ocean floor structures – including the abyssal plain, volcanoes, seamounts, mid-ocean ridges, and guyots, and the continental shelf and slope etc., Solving the Puzzle Under the Sea: Marie Tharp Maps the Ocean Floor by Robert Burleigh and Raul Colon, Water Land: Land and Water Forms Around the World by Christy Hale, modeling clay (damp sand or kinetic sand would also work) in multiple colors, rounded toothpicks, sticky address labels, black flair pens, 4.25” x 11” cardboard, data collection sheets showing depths of the Northeast Pacific Ocean, 8.5” x 14” grid paper, internet access, pencils, colored pencils
Engage
Introduction
Ask: What are the structures of the ocean floor, which forms 70% of the face of our planet.? What are the geologic processes that shape the seafloor?
Say: In this unit, we will learn about structures that comprise the ocean basins, the geologic processes that shape the landscape of the seafloor, how scientists and engineers use data-collecting instruments to gather information about the seafloor, and finally about an amazing, dynamic underwater volcano, Axial Seamount: the largest and most active volcano off of North America.
Say: The Circum-Pacific Belt is nicknamed "The Ring of Fire" because most of Earth’s volcanoes and earthquakes take place along this circular path. In addition to >100,000 underwater volcanoes and seamounts, our ocean hosts several structures similar to what we see on land. For example, the Great Plains on land and the abyssal plains, which cover most of the ocean floor.
Give students several minutes to interact with the images, Ring of Fire animation, and the Juan de Fuca Interactive map – have them list what they notice and what they wonder.